A Study on the Cure of the Siloxane-Modified Epoxy Resins

摘要

Siloxane-modified epoxy resins were studied in this research. The modified epoxy resins were cured with 3 mol% of 2-ethyl-4-methyl imidazole (EMI-24). The curing kinetics and the physical properties of the network were characterized using DSC and FTIR methods. The thermal stabilities of epoxy resins were obtained through TGA measurement. The fracture toughness was measured through double torsion tests. The fracture analysis shows that the siloxane-modified epoxy resin has a higher fracture toughness (by 140%) and rougher fracture surface than the unmodified epoxy. The modified resins also show better thermal stabilities and longer pot lifes than unmodified resins. The cure of siloxane-modified epoxy resin followed the first-order reaction kinetics. The glass transition temperatures of modified epoxy resins were obtained.